My first 5e Build: Tactical Assault Bear

[bhu]

Race:Kalashtar
Str 13, Dex 10, Con 12, Int 10, Wis 16, Cha 15 (point buy)

First 3 levels in Barbarian (Totem Warrior: Bear)
Next 6 Levels in Druid (Circle of the Moon), Sentinel Feat
Next 3 Levels in Fighter (Echo Knight)
Next 7 Levels in Paladin (Oath of Conquest), Piercer and Slasher Feats
Last Level in Barbarian, Alert Feat

The plan once i get enough levels is:

Round 1: Use Bonus Action to Wild Shape
Round 2: Use Bonus Action to Manifest Echo
Round 3: Use Bonus Action to Rage

So now I'm a bear (or something), I can use the Echo (and the Paladins Aura)  to ensure I keep Rage, I have resistance to all damage when raging, and when I crit I can burn spells for Divine Smite.  I might switch out some Feats to raise stats.  Sound feasible?

[Skyrock]

You are spreading your character very thin by skipping high-level features, becoming MAD (you need both Cha and Wis to multi-class into Paladin) and skipping ability score increases (very vital under bounded accuracy!), all for a buff routine that takes you three rounds to complete and allows you the gimmick to turn into a CR2 animal with Rage. The Brown Bear(CR1) and Polar Bear(CR2) lose their luster at mid-levels quickly even with Rage - you are very hittable at AC 11/12, and even the damage resistances of Bear totem Rage make your 34/42hp merely a speed bump.

Once you fall out of Wildshape through damage, you are in a sorry shape to participate in melee with your poor ability scores. Shillelagh cantrip could help a bit to make your melee attacks depend on Wis, and you could trade spell slots for smites, but it would still be... meh.

[bhu]

Well, it was intended to be a goofy gimmick build, but I take your point.  I'll drop Paladin and put the levels elsewhere, and redo the stats.

[bhu]

trying it as a slightly more serious class wifout the Paladin levels:

Race:Kalashtar
Str 16, Dex 12, Con 14, Int 10, Wis 16, Cha 9 (point buy), asi added in
First 5 Levels in Fighter (Echo Knight), Fighting Style (Superior Technique: Menacing Attack), +2 Con
Next 3 levels in Barbarian (Totem Warrior: Bear)
Next 6 Levels in Druid (Circle of the Moon), Sentinel Feat
Next 6 Levels in Fighter, +2 Str, +2 Wis

[Surreal]

trying it as a slightly more serious class wifout the Paladin levels:

Race:Kalashtar
Str 16, Dex 12, Con 14, Int 10, Wis 16, Cha 9 (point buy), asi added in
First 5 Levels in Fighter (Echo Knight), Fighting Style (Superior Technique: Menacing Attack), +2 Con
Next 3 levels in Barbarian (Totem Warrior: Bear)
Next 6 Levels in Druid (Circle of the Moon), Sentinel Feat
Next 6 Levels in Fighter, +2 Str, +2 Wis

Mild necro, but wanted to toss some thoughts on here.

An alternative to going Kalashtar Bear Totem is to spend a feat on Gift of the Chromatic Dragon which gives you a non-spell Absorb Elements a few times a day meaning it's useable while raging. It's not quite as good as Beat totem, but it covers a very good range. That opens you up to more interesting totem options, or Ancestral Guardians, or Beast claws for a blitzful of attacks with action surge.

Your Echo doesn't have a time limit, so pop one out during any downtime and you won't have to spend the bonus action in battle for it.

Druid overall is a bit of a trap for barbarians despite what people say. Moon Druid barbarian doesn't really work despite people online gushing over it. Maybe it's because those who do only play tier 1 where yeah ok your attack stats are nice, but into tier 2 it's lousy until you can tough it out until you get elemental forms in tier 3... but combined with your barbarian levels you're already behind the curve by the time you get those anyways so you're going from being really sucky to slightly less suck. Some utility forms are ok though, like Moorbounder for the high speed. Other druid subclasses aren't much better unless you're going for the utility. Spores druid is always a trap because the main feature eats up an entire action. Stars druid with the archer form gives you a ranged attack, but chances are you'll be pulling sneaky teleport shenanigans with your echo every turn anyways which kinda mitigates the need for ranged attacks. Oddball tech though, if you're running Ancestral Guardian barbarian then the archer form could proc your ancestral protectors. Wildfire Druid gives you the bonus action teleport too, with the added benefit that it can bring someone other than you along for the ride which can be very much worth it depending on your party composition.

In one of my current games, I'm a Beast barbarian taking levels into Echo, and possibly Gloom Stalker ranger in the late game. The plan is for a first strike action surge for 10 attacks (using the first two for rage advantaged shove to prone then grapple so my followup attacks will have advantage without needing to reckless), and I can either do that from my echo or use the echo to protect me from others that approach. Late stage feats that I'm considering are Gift of the Chromatic Dragon (for pseudo absorb elements), gift of the Metallic Dragon (for pseudo Shield), or Slasher to for the stat bump, decreased enemy speed, and giving them disadvantage after I crit which is fairly consistent with my high number of attacks.